No centering Problem column in submission result
Remember last submit language
Fix bug: original_id of poj unchanged after rejudge
Fix a bug of authorizing submission show
Set footer in the file not ENV
Update TODO
Init level exp settings after change max level and update them after create/edit program
Show exp info in current level page
Update TODO
Primitive exp-based level system
Merge pull request #2 from AlphardWang/development

fix : let admin see hidden problems
Change user exp after edit problem exp
Filter hidden problems' submissions from submission index
Merge branch 'development'
Do not count hidden problems' exps
Fix bug: cannot get failed problem in user page if accepted is empty
Modify sign in and sign out hint in devise links
Choose submission language via inline radio buttons
Cancel workaround on radio inline problem for chrome
(chrome 26 fixed the bug)
add modal for problem page